Chapter Three:  Equations

Take notes on the following topics.

Chapter Three

Section 3.1

Section 3.2

Section 3.3

Section 3.4

Section 3.5

Section 3.6

Section 3.7

Section 3.8

Section 3.9

Section 3.10

Section 3.11

Section 3.12

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Section 3.2 :  Multiplication Property of Equality

Vocabulary

• equivalent equation

• replacement set

• Multiplication Property of Equality

• Division Property of Equality

Example

Given the equation                      x/(-3) = 5

Multiply each side by -3.       (-3)[x/(-3] = 5(-3)

Simplify.                                            x = -15

Check.                                             x/(-3) = 5

Substitute -15 for x.                     (-15)/ (-3) = 5

Simplify.                                                   5 = 5 (true)

Thus, the solution is -15.

 

Division Property of Equality

For all real numbers,  a, b,  and  c,  if a = b, and c does not equal 0,    then  a/c = b/c. This means that dividing each side of an equation by the same nonzero number produces an equivalent equation.

Example

Given the equation                    -8x = 72

Divide each by -8.            (-8x)/(-8) = (72)/ (-8)

Simplify.                                      x = -9

Check                                      -8x = 72 

Substitute -9 for x.                  -8(-9) = 72

Simplify.                                     72 = 72 (true)

Thus, the solution is -9.

Take class notes.

Before starting your homework, rework the examples that are illustrated in this section of your textbook and the examples that I demonstrated in class. 

Then do your homework.

Write down questions (examples or concept that you do not understand).......then.............. Ask these questions in class.